Aims.To understand the contribution of active region and flare
plasmas to the λ195 channels of SOHO/EIT (Extreme-ultraviolet
Imaging Telescope) and TRACE (Transition Region and Coronal
Explorer).

Methods.We have analysed an M8 flare simultaneously observed by
the Coronal Diagnostic Spectrometer (CDS), EIT, TRACE and RHESSI. We
obtained synthetic spectra for the flaring region and an outer region
using the differential emission measures (DEM) of emitting plasma
based on CDS and RHESSI observations and the CHIANTI atomic database.
We then predicted the EIT and TRACE count rates.

Results.For the flaring
region, both EIT and TRACE images taken through the λ195
filter are dominated by (formed at about 20 MK).
However, in the outer region, the emission was primarily due to the
, with substantial contributions from other lines. The
average count rate for the outer region was within 25% the observed
value for EIT, while for TRACE it was a factor of two higher. For the
flare region, the predicted count rate was a factor of two (in case of
EIT) and a factor of three (in case of TRACE) higher than the actual
count rate.

Conclusions.During a solar flare, both TRACE and EIT λ195
channels are found to be dominated by
emission. Reasonable agreement between predictions and observations is
found, however some discrepancies need to be further investigated.

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